Electrolytic apparatus



Feb. 19,- 1929. i 1,702,924:

W. G. ALLAN ELECTROLYTIC APPARATUS Original Filed Nov. 10, 1923 8 Sheets-Sheet 1 Q w INVLNTTOR" ATTORNEYS.

Feb. 19, 1929.

W. G. ALLAN ELECTROLYTIC APPARATUS Original Filed Nov.10, 192:5 8 heets-Sheet 2 Feb. 19, 1929.

'W. G. ALLAN ELECTROLYTIC APPARATUS 8 Shets-Sheet 3 Original Filed Nov. 10, 1923 l/VVLNTOR. Y /%M/ v ATTORNEYS.

8 Sheets-Sheet 4 W. G. ALLAN ELECTROLYTIC APPARATUS Original Filed Nov. 10, 1923 Feb. 19, 1929.

Feb. '19, 1929.

' W. G. ALLAN ELECTROLYTIC APPARATUS Original Filed Nov. 10, 1923 8 Sheets-sheet 5 Feb. 19, 1929. 1,702,924

w. ca. ALLAN ELECTROLYTIC APPARATUS Original Filed Nov. 10, 1923 8 Sheets-Sheet 6 W. G. ALLAN ELECTROLYTIC APPARATUS Feb. 1 9, 1929.

Original Filed Nov. lO, 192:5 8 sheets-Sheet 7 11v V/iN 701a. 6 V y W A TTOR/VEYS.

Feb. 19, 1929. 1,702,924

' W. G. ALLAN ELECTROLYTIC APPARATUS Original Filed Nov.l0, 1925 8 Sheets-Sheet 8 I INVENTOR.

ATTORNEYS.

' Patented Feb. 19, 1929.

UNITED STAITESPAITENT OFFICE. I

Application filed November 10, 1928, SeriallNo. 674,048.

The invention relates to ap for electrolytic production RONTO, ONTARIO, CANADA,

ASSIGNOR, BY MESNE ASSIGH- MENTS, TO IARLEY G. CLARK.

' ELECTROLYTIC APPARATUS.

paratus adapted of materials or substances in the solid, liquid or gaseous state, and described herein is inten and while the apparatus illustrated ded for the purposes of electrolytic decomposition of an electrolyte into its gaseous into such parts of 1ts cons constituents, or tituents as Wlll appear at the electrodes in gaseous form, as

for example,

an aqueous solution of an acid or an alkali whence may be produced oxygen and hydrogen gases, limited to such use, but may the art of electrolysis gener The objects of the invcn prove and cheapen the invention is not be employed in' ally.

tion are to imthe construction, and to increase the efliciency of apparatus of-the character described; to provide an apparatus which is compact; which is of rugged construction; which will not easily will be easy of repair; which will be flexible; which will occupy,

of order; which a relatively small. superficial and cubical space; and wherein the rate of gas production, and in consequence the forces taties of energy to be dealt with, are very great.

A further object is and quanto provide means for separating out the three phases of matter,

solid, liquid and and to provide means oneior more of said phases, 7 I turn of one or more of them to the apparatus.

A further object isto provide means regulating, controlling, and lncreasing gaseous, of the electrolyte, I

for the withdrawal of and for the refor the purity of the electrolytic products, and for regulating, controlling, and in some cases equalizing, or

tending to equalize,

the densities of-the electrolytic solution which may tend to become different in different parts of the apparatus.

A further object is to p relieving the apparatus 0 rovide means for accumulations of electrolytic or other products which may tend to collect in the apparatus.

A further object is to insert at various points in the apparatus, insulating means whereby efficient operation and purer-products will be assured, and which will guide through the apparatus,

.the flow of current and which will prevent, orrents.

These and further objects limit stray ourwill more fully get out sulating joint.

Each group preferabl in a group,

Renewed May 23, 1927.

appear in the following specification and accompanying drawings considered together or separately.

Reference is Patent Nos. 1,464,840 and 1,592,512 issued to me under the dates of August 14th, 1923, and July 13th, 1926, respectively..

i The drawings illustrate one embodiment of the invention, in which like parts in all the several figures are designated by corresponding characters of reference and in which Fig. 1 is a side elevation of an apparatus embodying the invention.

Fig. 2 is an end elevation of the same.

Fig. 3 is a top plan view illustrating a portion of the piping.

. Fig. 4 is a plan view of a portion of the apparatus partly in section, the section being taken on the line 4-4 of Fig. 1.

Fig. 5 Fig. 1.

Fig. 6 1s a detail sectional view showing a modi fication.

Fig.7 is a detail side elevation, partly in section, of a cell group. Fig. 8 is a section on Fig. 7

Fig. 9 is a detail View in. side elevation the line 88 of is a section on the line 5,-5 of here made to U. S. Letters of a form of cooling, bubbling and washing element of the apparatus.

Fig. 10 is a'modificatlon of" the same.

Fig. 13 is a detail view'of a sight and in- Fig. 14 is a detail plan view of areturn manifold.

Fig. 15 is a side elevation of the same. Fig. 16 is an end elevation of a pipe insulationsection, and r Fig. 17 is a'longitudinal line 19--19 of Fig. 16. In the embodiment of the invention illustrated, the apparatus comprises aplurality of cell groups A arranged in electrical series. comprises a plurality of cell units B. he number of units and the number of groups section on the in the apparatus desired. In the. drawings each unit comprises a cell wall or partition of may be varied asthin sheet steel, for example, clamped between the inner flanges 2 of twoframe members 3. The members 3 are each provided with an outer flange 4 as shown. Each wall, except those forming the end walls of the group of units, carries on each side thereof an electrode of any suitable form. Each end wall of the group carries one electrode. When the units are assembled a porous diaphragm 5 is clamped between the flanges 4 of adjacent units. The diaphragms 5 and partitions l alternate throughout the group, and an electrode is positioned parallel to and in close proximity to each face of each diaphragm whereby when the cell spaces between the partitions are filled with a suitable electrolyte, and an electric current is passed through the group, oxygen will be formed at the anode and hydrogen will be formed at the cathode. The anolyte cell space of one unit is separated from the catholyte cell space of the adjoining unit by a diaphragm 5 through which the electrolyte may pass, but which will prevent the passage of, the gas.

Figs. 1, 3 and 4 of the drawings illustrate two groups of units, but it is to be understood that any desired number of units connected in series may be employed. The drawings show six units in each group, but this number is merely illustrative, and is selected for the reason that a group 'of such size may be easily handled.

Each anolyte frame member 3 is provided with two openings 6 and 7 and each catho-' lyte frame member 3 is provided with-two openings 8 and 9. A return flow manifold 10 is in communication with the openings 6 of each group. A similar manifold 11 is in communication with the openings 9 of each cell space out each group. A manifold 12 is in communication with all of the openings 7 and a manifold 13 communicates with the interior of the cells through the openings 8 of each group. The openings 8, and the manifold 13 are of greater capacity than the openings 7 and manifold 12.

A tubular riser 14 leads from each mani fold 12 and connects with an oxygen-anolyte header 15, and a tubular riser 16 leads from each manifold 13 to a hydrogen-catholyte header 17. The headers 15 and 17 are positioned some distance above the tops of the cells as shown in Fig. 1. The header 15 connects with the upper part of an oxygen separating tank 18, and the header 17 enters the upper part of a hydrogen separating tank 19. c

The manifold 10 communicates with a header 20 which is in communication with the lower part of the tank 18, and the manifold 11 is connected to a header 21 which enters the lower portion of the tank 19. These main headers 15, 17, 20 and 21 serve the combined purpose of conveying the lyte will not move. contrary to the path of i the ascending gases.

The discharge from the headers 15 and 17 into the tanks 18. and 19 respectively is through insulating pipe sections 22 and 23. The mixture of gas and electrolyte carried by the automatic gas-lift action over into the tanks, will be discharged above the level of the electrolyte in the tanks.

annular frame which latter is hung by wires 124 from a point or points close to the top of the tank. Each wire is provided with a loop whiclnengages over a projection on themside o'f the tank, and with a handle 125, whereby the screen may be taken out of the tank for, cleaning, renewal or any other purpose when the tank cover has been removed.

The object of the screens, which are preferably composedof a cloth woven of metal which will resist the action of the hot electrolyte and the nascent gases, is to cause the minute gas bubbles suspended in the electrolyte in a state of supersaturated tension, to coalesce to form larger bubbles which burst and allow the gas therein to mingle with the remainder of the gas and rise into the upper part of the tank, and the heavier electrolyte, and such impurities as may be present in the electrolyte, will fall to the bottom of the tank. As the electrolyte proceeds downward -in the tank it will lose such fine bubbles of gas which have passed through the screen, and which will coalesce and rise to the surface.

Towards the lower end of the tank 18, but above the bottom thereof, there is a valved outflow connection 25, and similar connection 26 leads from the tank 19. The connection 25 oii'ers communication with a .reditfusion tank 27,-and, by means of a valved branch 28 with the return header Suspended within each tank 18 and 19 is A 20. The connection 26 is similarly conadditional valved connection 30 betweenthe tank 27 and header 20 is provided, and I there is a similar valved connection 31 betweensaid tank and the header 2-1. If dey sired the electrolyte after being relieved of I *condense the moisture and entrained im ous points in the piping system,

trolyte may be ascertained, and similar thermometers 34 may be placed in the anolyte and catholyte headers 15 and 17 between the insulating joints 22 and 23 and the tanks 18 and 19. 1

Observation glasses 35, to be presently specifically described, may be placed at variglasses 36 on the tanks 18. and 19 and elsewhere in the apparatus will enable the operator to observe conditions in the system. In order' to promote circulation of the electrolyte and nascent gases through the system it is desirable that at some pointin the circulation system, the temperature of the gases, and intrained anolyte and catholyte be lower than that of the'electrolyte and gases in the cells wherebythe volume of the contentsof the system will be reduced either by the contraction thereof due to the lowered temperature, or to condensing effect. In the embodiment of the invention illus; trated, the reduction in temperature is effected in the separating tanks 18 and 19, but it is to be understood that the cooling chambers may be placed elsewhere between the cells and the said tanks.

Preferably the upper portions of the tanks, in which the entrained electrolyte is separated from the gas by gravity, is maintained at a temperature lower than that of the body of electrolyte in the lower portions of the tanks. This may be accomplished by applying lnsulating lagging to all of the circulating system, except possibly the cells proper, and leaving the upper parts of the tanks 18 and 19 bare, whereby the room temperature will purities, such as NaOH or KOH and cause it to fall into the electrolyte in the lower portions of thetanks before the gases pass out by way of the pipe connections .64. In

. may

Fig. 5 the insulation 37 of the lower portions of If desired. the upper portions of the tanks, in which the gas separated from the electrolyte, may be cooled by :means of a water acket 38, as shown in Fig. 6, or by means of a coil through which cooling liquid 7 c rculate. v

The bottom of each tank 18 and 19 is preferably of conical form as shown, and

each is provided with a valve 118 whereby any solid or semisolidmat-ter may be withdrawn from the tanks, and each of said tanks is provided with a valved drain and be heated by means of a steam and gauge cells or piping, 'feed water will it threatens to collect to excess. 'of the settling chamber at the bottoms of stances,

the tanks is shown in dottedlines.

sampling connection 119 wherebysamples of electrolyte may be withdrawn for testing.

The feature of providing means for set tling, and the removal of solid matter, such as sludge, is of importance for the reason that it is often impossible to'secure commercial solvents for the caustic soda or caustic potash which are free from insoluble matter suchas silica, alumina, ferric hydrate, lime, magnesia, etc., and if such. substances in finely divided state are present, be carried over into the separating tanks, and will settle and be deposited in the conical bottoms thereof and be drained off at intervals. f

Likewise any solidymatter formed in the or any solid matter in the be thrown over into the bottoms of the tanks,

the tanks, it will to. use undistilled feed water and commercial solvents for the electrolyte without danger of clogging up the system.

Each of the headers 15, 17, 20 and 21 is subdivided into a number of flangedpipe sections, each of which is electrically insulated from each other section, by means of an insulating gasket 39. The flanges of the tube sections are secured together and to they will and be removed before 0 Because be possible, n many lIlthe gasket 39 by means' of bolts insulated from the flanges by insulating bushings 40. The gasket 39- is preferably of a material which will withstand the action of the hot electrolyte and the nascent ases, and which will have a slight degree 0% compressibility under the bolt pressure. -Compressed asbestos sheet packing is a suitable material for the purpose.

By subdividing the headers in the manner above described, and electrically insulating the several sections from one another, shunt currents are prevented, and the generation gases is reduced to negligible quantity. The number of subdivisions between any two groups-of cells in the embod ment of the invention illustrated, is two but the number may be increased, if desired, to secure better results.

Each return manifold 10 is in communication with all of the anode cell spaces of a cell group, and with the return header 20 by means of a valved pipe 41 having an observation tube therein.- The manifold 10 is also connected by means of a riser 42' to a of impure sections, to a relief chamber 44 situated at that end of the structure opposite the sepa- Each return manifold 11 is similarly c'on- I rating tanks 18 and 19.

relief header 43, composed of insulated pipe higher than any to which the level of electrolyte can rise in the course of operation of the apparatus, and'the tanks 44 and 46 are connected to the return headers 20 and 21 respectively by means of risers 47 and 48 each having a valve 49 therein, and each provided with a drain valve 50. H

llt will be seen that the return flow headers 20 and 21 from the separating tanks 18 and 19 to-the cells, and the cell offtakc headers 15 and 17 are on a higher level than the tops of the cell casing, and that the relief headers 43 and 45 and relief tanks 44 and 46 are at a higher level than the headers '15 and 17. Any gas which may form in, or find its way into, the electrolyte in the separating tanks or in the return flow connections, will be swept along by the flow of the electrolyte from the chambers and find egress to the relief chambers, and the electrolyte entering the cells will be free of gas. The relief chambers are, in the'embodimcnt of the invention illustrated, open to the atmosphere, but the gases from said chambers may be conveyed to a storage reservoir if desired.

The return flow manifolds 10 and 11 and the of'ftake manifolds 12 and 13 are connected to their respective cell spaces by means of insulating risers 51 each preferably provided with an observation'glass 35.

The construction and arrangement of the manifolds 10 and 11 is as follows The manifold, and its pipe 41 form a U- shape structure with the legs thcrepf horizontally disposed, with the pipe 41 lying directly below the return headerto which it is connected. The free end'of the pipc'41 is connected to the underside of the header, and a valve 52 is in the connection. Each manifold is provided with a plurality of depending nipples 53 each of which is. connected to a riser 51.

The risers 51 and the insulated pipe sections carrying the observation glasses 35 are preferably constructed as follows A heavy walled glass tube 54 is placed inaxial alinement between two pipe nipples 55 each threaded at its outer end; Covering each joint between the tube 54 and the nipp'les is a flexible or semiflexibl'e sleeve 56- of rubber or other suitable material each secured to the tube and a nipple by means of suitable hose bands 57. Secured to the threaded end of each nipple 55 is a union 58 by means of which the observation glasses may be secured in a pipe line. I

The subdivided headers 15, 17, 20, 21, 43 and 44 are supported by and insulated from a frame consisting of a series of pipe columns 59 arranged in the longitudinal center of the apparatus. Each header rests upon a block 60 of insulating material carried at .or near the end of a cross arm 61 clamped to the columns, and the relief chambers 44 and 46 rest upon insulating blocks on the cross arm 61 which supports the headers 15 and 17 at one end of the apparatus.

By clamping the cross arms (51 to the columns, the cross arms may be readily raised or lowered to adjust the levels of the various pairs ofheaders relatively to. the cells and to each other, to facilitate assembly and installation ofthe apparatus as a whole,,and also to permit of adjustment of the amount of the gas lift effect, and of other conditions of circulation and flow of the electrolyte and gases in the system, whereby various pressures, hydrostatic and others, may be balanced on one or both sides, anolytic or catholytic, of the circulating and generating systems. All of which is important to produce conditions effective in yielding gases, or other productsof reacting of a maximum degree of purity.

In order to place the headers 15,20 and 43, or any of them, on levels different from headers 17, 21 and 45, the insulating blocks 60 may be higher on one side of the center line of the. apparatus than on the other, or there maybe a separate cross .arm for supporting each header. instead of a single cross arm for supporting a pair of headers, as illustrated.

In connection with the apparatus above described the oxygen from the tank 18 may,

if desired, be passed to a cooling, bubbling,

and washing tank 62, and hydrogen may enter a similar tank 63. The tank 63 may be approximately double the capacity of the tank 62. The Washing, tanks are identical,

except as to size, and a description of one will sufiice for both. 4

Oxygen will leave the tank 18 through a pipe 64, provided with an insulating observation section 35, which enters the top of the tank'62 and terminates ata point a short distance above the bottom thereof. A screen -65, preferably of the same construction as the screens 24 in the tanks 18 and 19, is carried on the lower end of the pipe 64 and forms a foraminous diaphragm in the tank.

Water is admitted to the tank 62 by means of a valved pipe 66, and the water-in the tank is maintained at approximately a constant level by means of a standpipe 67in communication with the tank at the bottom thereof.- As Will be seen the level of the water in the tank will be considerably above the screen 65 whereby gasescaping froin the pipe 64 will bubblciip through the screen where the bubbles will be broken up, and the gas thoroughly washed before it is led off by means of a c'mnection 68 at the top ofthe tank. Each of the washing tanks is provided with a gauge glass, and said tanks are connectet together by means of a throttle valved communicating pipe 69, Aihving a valved waste outlet 70.

Another and bubbling and Washing device is illustrated preferred form of, cooling,

'standpipe,

' position relatively to the pipe 72.

in Figs. 10, 11 and 12. In this construction the oxygen and hydrogen tanks 62 and 63 are of practically the same construction as those above described, but instead of employing overflow weirs of fixed height the same may be adjustable, as shown. K

Each overflow weir comprises a stand pipe 71 in communication with its tank 62 or 63 and near the bottom thereof. The standpipe is closed at its bottom, and an overflow pipe 72 extends through the bottom and extends upward in the "'standpipe'.

A tube 73 is telescoped into the pipe 72 and is provided with a series of apertures 7 4 as shown. The tube is provided with a stem 75 which extends through the top of the and a set screw 76 may be employed to retain the tube in the desired tank will enter the stand pipe and rise to the level of the openings 7 4 and will then escape through the bottom of the'pipe. The adjustability of the tube 73 will be utilized to maintain the level of 'he liquid in the tank at any height desired.

The washing liquid from the Instead of employing a separate inlet pipe.

' 66 for each tank, as before described, a vertically arranged cylindrical tube 77, prefer-' located between the tanks 62 and 63, is The said tube is divided by means of a vertical partition 78 into two chambers 79 and 80. The tube is inserted in the pipe connection 69 between the bottoms of the tanks 62 and 63, the chamber 79 being in communication with tank 62 and the chamber 80 communicating with the tanks ably employed.

The top of the tube 77 is open and washing liquid, water for example, is supplied to the chambers 7 9' and 80, respectively, by means of faucets 81, 82. The bottoms of the chambers are in communication by means of balancing pipe connections 83 having a trottle valv'84- and a drain valve 85. The tube 77 is provided with a gauge glass 86 to indicate the level of the liquid in one or both of the chambers 79 and 80.

The electrodes employed in the apparatus may be of any suitable type, but preferably each electrode 87 is composed of a plurality of foraminous sheets or plates such for example as of woven wire cloth, the metal of which will not be affected by the electrolyte or by the temperature of the same.

v In the preferred electrode the foraminous sheets are fused together at their edges to form a solid border, and the said borders are united, as by welding, to 'studs 88 projecting from the plates 1 which form the partitions of the cell members. Each diaphragm'is composed of an insulating material which is of such a character that the electrolyte may pass freely through it, but which will prevent-the passage there- 4 15 and 17 and portions .of

through'of the gases which will result from the decomposition of the electrolyte or any part thereof.

Each diaphragmis composed of a sheet 5 of the material desired, in the present case a sheet of woven asbestos fabric, of a shape corresponding with the shape of the cell space as defined by the walls 3. I

The flanges 4 are provided with openings therein, and, when the cells are assembled, these openings are in alinem'ent, and bolts 95. are passed through all of the flanges of each' grou), the said bolts being insulated from the anges by'means of washers 96, and spacing collars 97 are threaded on the bolts between the flanges of each pair of, cell frames 3.

The operation is as follows:

. The cells are filled with electrolyte, example an aqueous solution of an acid or an alkali, which will, when the electrolyte is quiescent, stand above the tops of the cells in the outlet and return risers. A suitable electric current is passed through all of the cells in the apparatus to produce gases (oxygen and hydrogen) by the decomposition of the electrolyte.

The formation of the gas or gases, and the heat imparted to the electrolyte by the high current density of the electric current, and by the extraneous heating means when employed, will result in an increase in the volume of the combined electrolyte and gases whereby the same will rise above the normal quiescent level in the ofi'take risers and manifolds 12 and 13 and into the ofi'take headers flow along the same until the anolyte reaches the separatin chamber 18, and the catholyte, reaches t chamber 19, where the greater part of the gases will be separated from the electrolyte by gravity, and anolyte or catholyte, as the case may be, will accumulate in the lower the chambers 18 and 19 respec tivcly, and the level of the liquid in .the separating chambers is maintained below the as for points 'of discharge into said chambers filters 24 will cause the bubbles, suspended in the electrolyte in a state of supersaturated tension, to coalesce'and form larger bubbles which break and allow the as therein to mingle with the remainder o the gas, and rise into the upper parts'or domes of the chambers.

The electrolfyte after passing through the screens will all downward, and any entrained bubbles of gas which may assed through the screens rom the liquid and pass upward through have may separate the screens and comingle with the gases in the domes.

Any solid matter in suspension in the electrolyte in the chambers will settle and collect in the conical bottoms of the chambers, and be drawn 016? from time to tim through the valves 118.

The process of ejection of electrolyte and gases from the cells and into the separating chamber is continuous as long as the electric current flows, and it is substantially proportional to the gas lift effect ofthe oxygen and hydrogen on the anolytic or catholytic sides respectively of the circulating system, and, by reason of the proportional buoyancy of said gases, is greater for the hydrogen than for the oxygen. The volume of electrolyte carried from, the cellsto the separating chambers, in a given time, varies with and is approximately proportional to the volume of gas generated in a given time, or in other words, is proportional to the current flowing.

The result of discharging the electrolyte into the separating chambers is to produce a greater hydrostatlc head therein than the hydrostatic head within the cells, and, as the electrolyte is free to return to. the cells. through the insulated pipes 25, 26,. tank 27,

headers 20, 21 and manifolds 10 and 11, the

flow of the electrolyte is automatic, and proportional to the combined effects of the gas-. .lift of the generated gases and the electric 'current. The increase of hydrostatic .head

- in the separating chambers, and hence the flow is greater on the hydrogen than on the oxygen side of the system. This, is of advantage for the reason that the volume of hydrogen liberated at the cathodes is twice that of the oxygen liberated at the anodes.

The electrolyte in passing from the chambers '18 and 19 pass into the redifi'using tank 27 and are heated ,by means of the steam coil 32. Feed water to compensate for that which has been decomposed'in the cells is admitted to the tank 27 through the threeway .valve 27 in the bottom of said tank,

Other and more complicated phenomena occur, such as the balancing of the endosmoticv pressures through the diaphragms with the unbalanced hydrostatic pressures on the anolytic and catholytic sides respective- 1y, which would continually tend to reestablish a uniformity of level of the electrolyte through the rediflusion tank, were it not for the said endosmotic pressure. The endosmotic pressure may-be described as a force set up'by and due to the actual forcing of ions through the pores of the diaphragm by the passage of the electric current.

Any gas which may be retained in the electrolyte after the latter has passed from the tanks 18 and 19 will escape through the risers 42 to the headers-43 and 45, and thence to the tanks 44. Any electrolyte entrained moaeaa with such gas or gases may be returned to the headers 20 and. 25 by means of the pipes 47 and 48.

The gases in the domes of the chambers 18 and 19 may be drawn off in oxygen and hydrogen holders respectively, but when gases of a high degree of purity are required the gases from the domes pass through pipes 64 into the washing and cooling tanks 62 and 63 respectively, in which the gas is washed and cooled.

The gasescaping through the lower open end of the extension of the pipe64 will bubble upward through the wash water in the tank and will pass upward through the screen 65 being broken up into fine bubbles, globules or particles, and will be washed and cooled by the subdivided contact with the wash water, as well as by the contact with the wetted and cooled wires of the screen. The gas thenrises to the ,upper portion of .the tank, whence it may be conducted to any suitlable gasholder, compressor or storage tan r.

The height to which the wash water will stand in the cooling tanks will depend upon the pressure of the gases above the surface of the water, the height of the overflow weir 67, and and atmospheric pressure.

In addition to washing and cooling the gases,the connected tanks 62 and 63 also act to maintain the pressures of the gases equal, or bearing some definite relation to each other.

e If the gases withdrawn from the tanks 62 and 63 are to be compressed, the compressors for the oxygen, and hydrogen respectively may notbe compressing at the same time,

orthey may be compressing at rates which do' not bear the same ratio to one another as do therates at which the gases are being generated in the cells, namely; one volume of oxygen to two volumes of hydrogen.

'Such unequal suctions of. the compressors lower than the pressure in oxygen tank 62, due to the inadequacy of gas supply, or

for other reasons. The result of this would be that, with the valve in the connection 69 wide open, water would flow from tank 62 to tank 63, and the hydrostatic head in tank 63 would be higher than the head in tank 62, the flow of hydrogen into the tank 63 would be lessened by the column of water therein, and the flow of oxygen would beincreased because of the low head. This unbalancing of the gas pressure would be felt in the electrolytic cells and apparatus with undesirable results. By operating the valve vpatent in the balancing connection 69 as a throttle, the hydrostatic heads in the tanks may be maintained at the desired levels.

In accordancewith the provisions of the statutes, I have described the principle of my invention together with the apparatus which I now consider to represent the embodiment thereof, but it is desired to have it understood that the apparatus shown is merely illustrative and that the invention may be carried out in other Ways.

The invention having been described, what is claimed as new and desired to be secured by Letters Patent, is as follows 1. An electrolytic apparatus, comprising two closed systems containing electrolyte, each system comprising cells, a separating chamber and conduits connecting the cells and chambers, porous diaphragms separating balsaid systems within the cells, means for ancing the endosmotic pressure produced by the flow of current through the electrolyte in the pores of said diaphragms with the difference in hydrostatic pressures produced in the two chambers belonging particularly to said two systems, and a redifiusing tank common to both of said systems.

I 2. An'electrolytic apparatus, comprising two closed systems. containing electrolyte, each system comprising cells, a separating chamber and conduits connecting the cells and chambers, porous diaphragms separating 'said systems within the cells, means for balancing the endosmotic pressure produced by the flow of current through'the electrolyte in the pores of said 'diaphragms with the difference in hydrostatic pressures produced in the two chambers belonging articularly to said two systems, and a rediii u common to both of said systems, said rediffusing tank being provided with return flow conduits connecting the same with and in the path of the electrolyte between the separating chambers and cells.

3. An electrolytic apparatus, comprising two closed systems containing electrolyte, each system comprismg cells, a separating chamber and offtakeconduits connecting the cells and chambers for-conveying thegenerated products to the separating chambers, porous diaphragms separating said systems within the cells, means for balancing the V endosmotic pressure produced by the flow of current through the electrolyte in the pores of said diaphragms with the difference in hydrostatic pressures produced in the two chambers belonging particularly to said two systems, a rediffusing tank common to both said systems, 'return flow conduits connecting the separating chambers, redifiusing tank and cells so as to position the tank in a ath of the electrolyte between the cham ers and cells, and means for heating the redifiusing tank.

sing tank ,sulated from the columns,

bers, porous 4. The combination in an electrolytic apparatus of an electrolytic cell comprising an anode side and a cathode side, an anolyte separating chamber in communication with the anode side, a catholyte separating chamber in communication with the cathode side, conduit means for returning electrolyte from said chambers to the cells, oxygen being columns arranged in the longitudinal centerof the apparatus, adjustable cross arms carried at'difierent heights on the columns, the anode side of each cell in each group being provided with the tubular riser, all of said risers communicating with an anolyte header, the cathode side of each cell of each group being also provided with a tubular riser, all ofthe last-mentioned risers communicating with the catholyte header, an

amber, a catholytic anolyte separating ch separating chamber, said headers communieating respectively with catholyte chambers, each of said headers being supported upon and insulated from a cross arm, a

tank for receiving electrolyte from said chambers, headers for conveying electrolyte from said tank to each cell unit,

said headers being supported upon and insulated from cross bars carried on the colun'ms, gas headers carried on and inand auxiliary headers ofi'ering communication between the electrolyte return headers and the said gas headers. K

6. An electrolytic apparatus comprising two closed systems containing electrolyte,

each system comprising cells, a separating chamber and oiftake conduits connecting the cells and chambers for conveying the generated products to the separating cham-- diaphragms separating said systems within the cells, the hydrostatic heads in both systems to means for ad usting the anolyteand balance the endosmatic pressure within the cell produced by theflow of current through the electrolyte in the pores of said diaphragm, a redifiusing tank for the returning electrolyte, and return flow conduits con-. necting the tank, se arating chambers and cells .for returning t e 'separatedelectrolyte to the cells 7. In an electrolytic cell, the combination duits above the level of the electrolyte with anode and cathode compartments, and in thecell compz't'rtments to thereby regulate a vporous diaphragm therebetween, of anolyte the total pressures in the anode and cathode and catholyte separating chambers associated compartments. 4

5 therewith, conduit means joining the com- This specification signed this sixth day of pztrtments and chambers respectively, and November, 1923. r means for adjusting the heights of the con- WILLIAM G. ALLAN, 

